Section 5.2- Gas Pressure Flashcards
since gas molecules are in constant, rapid motion, they have
kinetic energy
equation for kinetic energy
KE= 1/2 mv^2
the collisions of the gas molecules with the container walls constitute __________, defined as a force (push) per unit area
pressure
pressure equation
P=F/A
more important in the KE equation
velocity because it is squared
the SI unit for pressure
pascal (Pa)
the more velocity an object has, the greater the _____________ and _____________
kinetic energy
temperature
directly related to kinetic energy
pressure
1 Pa is a _________ per square meter
newton (SI unit of force)
the pressure exerted by the collisions of gas molecules in our atmosphere with the earth may be measured by a
barometer
invented the mercury barometer
Evangelista Torricelli
a more compact and rugged type of barometer that senses pressure using a flexible, airtight metal box
aneroid barometer
pressures in __________________ are convenient because they can be directly measured using mercury barometers and other similar devices
millimeters of mercury
is equal to 1 mmHg but is precisely defined in terms of the pascal
torr
is average air pressure at sea level
equal to 760 torr
standard atmosphere
another term denoting 1 atm or 760 torr is
standard pressure
another unit used for atmospheric pressure (especially in meteorology) is the __________, equal to 10^5 Pa
bar
a common laboratory device used to measure the pressures of gas samples is the
manometer
the two types of manometers
open-end manometer (one end open to atmosphere)
closed-end manometer (has a vacuum; not depend on atmospheric pressure)
small gas pressures can be measured more accurately by using the
closed-end manometer
